JP3442378B1 - Molding method and molded article using foamed resin elastic particles - Google Patents

Abstract

Abstract: PROBLEM TO BE SOLVED: To provide pillows, cushions, mats, etc., which are required to have a high air permeability, a stable shape, and
Provided are a molded article having good water permeability and water absorption and a molding method thereof. SOLUTION: A cutting and granulating step of granulating the foamed resin elastic body into a predetermined size at room temperature using a cutting means, and adding a urethane prepolymer as a binder to the elastic granules 11 obtained in the step. Step, a step of arranging a polyurethane sheet prepared in advance on the lower mold contact surface side, a step of filling the elastic granules 11 containing the urethane prepolymer, and placing the upper mold with the polyurethane sheet covered on the upper part Thermoforming in the presence of steam
And a molded article obtained by the method.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a foamed resin elastic particle which is highly breathable and has a soft touch and elasticity while maintaining the stability of the shape, and which is most suitable for pillows, cushions, mats, etc. The present invention relates to a molding method used and a molded body obtained thereby.

[0002]

2. Description of the Related Art An attempt to make a molded body such as a pillow, cushion, or sofa by solidifying elastic synthetic resin particles is found in, for example, Japanese Patent Laid-Open No. 58-142836. This is one in which a rubber chip contains an organic acid halogenide and is bonded and integrated with a binder made of a prepolymer having an isocyanate group at the molecular end.

[0003]

Granulation of elastic synthetic resin from a large solid is difficult. As a commonly used means, there is a method of crushing an elastic synthetic resin by giving a destructive force at a low temperature. However, this conventional method requiring refrigeration equipment has a problem in terms of cost. In particular, such as polyurethane foam, which is inexpensive and bulky, is not suitable for granulation.

[0004] In addition, the molded body which uses only the binder of the granulated elastic synthetic resin has unevenness on the surface of the molded body, has a feeling of contact with the surface, and has an appropriately soft touch and elasticity. Is difficult. Therefore, in order to hide the irregularities on the product surface, there are many cases where painting or covering with a synthetic resin cover or the like is performed, but this is a factor that impairs air permeability and the soft touch is often lost.

Therefore, the present inventor has investigated a molded body which is required for pillows, cushions, mats, etc., which has a high air permeability, is stable in shape, and has good water permeability and water absorbability, and a molding method thereof. .

[0006]

[Means for Solving the Problems] As a result of examining the above problems, a cutting granulation step of granulating a foamed resin elastic body into a predetermined size at room temperature by using cutting (scissors) means, A step of adding a urethane prepolymer as a binder to the obtained elastic particles, a step of arranging a polyurethane sheet prepared in advance on the lower mold contact surface side, and a step of filling the elastic particles containing the urethane prepolymer. A molding method using a foamed resin elastic granule comprising a step of placing an upper mold in a state of covering the polyurethane sheet on the upper part and performing heat molding in the presence of steam. Examples of the foamed resin elastic body include polyolefin foams such as polyethylene, polyurethane foams, etc. Among them, polyurethane foams are preferable from the viewpoint of elasticity, shape stability, soft touch, and the like.

The foamed resin elastic body is made into particles at room temperature by using a cutting (scissors cutting) means. As the cutting means, a device having a large number of scissors blades is used to simultaneously cut,
The expanded resin elastic granules thus obtained have a particle diameter of about 4 to 8 mm square. The flat foamed resin elastic body can be made into granules, or the filaments can be cut into granules. Since it is cut, it becomes a crushed bed and has a smooth cross section, which contributes to adhesion in a later step.

The urethane prepolymer of the binder is
It is a urethane prepolymer having an isocyanate group at the molecular end. Examples of the organic polyisocyanate used for producing the urethane prepolymer having an isocyanate group at the molecular end include aromatic polyisocyanates such as 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 2,4-toluene diisocyanate and 2 , 6-Toluene diisocyanate, xylylene diisocyanate, diphenylmethane-4,4 '
-Diisocyanate (MDI), diphenylmethane-
4,4'-diisocyanate and diphenylmethane-2,
A mixture with 4'-diisocyanate, a modified polyisocyanate based on diphenylmethane-4,4'-diisocyanate, alicyclic polyisocyanates, and
Mixtures of two or more of these may be mentioned. Among these, aromatic polyisocyanates are preferable.

As the polyol used for producing the urethane prepolymer by reacting with the above-mentioned organic polyisocyanate, a high molecular weight polyol such as polyether polyol, polyester polyol, polymer polyol, polybutadiene polyol and two kinds of these are used. Mixtures of the above are included. As the polyether polyol, low molecular weight polyols (bifunctional polyols such as ethylene glycol, propylene glycol, 1,4-butanediol and 1,3-butanediol; trifunctional or higher functional polyols such as glycerin, trimethylolpropane and pentaerythritol). Etc.), ring-opening polymerization products of alkylene oxides (such as polytetramethylene ether glycol), and polyester polyols such as polycarboxylic acid (aliphatic polycarboxylic acid,
For example, polyester polyols and lactone polyesters (polycaprolactone polyols) obtained by condensation of adipic acid, maleic acid, dimerized linoleic acid, aromatic polycarboxylic acids such as phthalic acid) and polyols (the above-mentioned low molecular weight polyols or polyether polyols) Examples of the polymer polyol include polyols (polyether polyol, polyester polyol, etc.).

When the polyisocyanate and the polyol are reacted to produce a urethane prepolymer having an isocyanate group at the molecular end, the polyisocyanate is used in excess of the equivalent amount, and the obtained urethane prepolymer is used. When the content of the isocyanate group is low, the bonding strength of the foamed resin elastic particles becomes weak, and when the content of the isocyanate group becomes high, the elastic body containing the binder becomes hard, which causes problems such as brittleness. A urethane prepolymer having an appropriate property can be selected and used.

The urethane prepolymer may be used in an amount of 10 to 12 parts based on 100 parts of the expanded resin elastic particles used, as long as it is sufficient for bonding the expanded resin elastic particles. If it is more than 13 parts, the porosity will be impaired and it will become hard, and if it is less than 9 parts, the binding force between the expanded resin elastic particles will be weak.

The molded body obtained by this molding method is
The core layer is a solidified layer of the foamed resin elastic particles with a urethane binder, and the surface layer is a polyurethane foam layer. pillow,
The shape of the cushion or mat can be freely selected. In particular, when the core layer and the surface layer are formed of a foamed resin elastic particle having continuous pores, the air permeability is good, and the water drops down in a short time by simply pouring water from the top. It is possible to smoothly wash with water.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION An ether-based polyurethane continuous foam block 10 (see FIG. 5, Kurashiki Spinning Co., Ltd., trade name "Super Soft Foam") is cut as a foamed resin elastic body by a device having a large number of scissors blades. Then, the foamed resin elastic particles 11 having a particle diameter of approximately 4 to 8 mm were simultaneously prepared (see FIG. 6).
reference). That is, it is a cutting and granulating step of granulating into a predetermined size at room temperature using a cutting means.

Next, the polyurethane elastic granules obtained in the above step were mixed with a methylene chloride solution of a TDI (tolylene diisocyanate) type urethane prepolymer as a binder (resin content 60%, manufactured by Sanyo Chemical Industry Co., Ltd., product name " SGI-2000 ") was mixed with 120 g per 1 kg of elastic particles to prepare a core material in advance.

12mm in the lower mold that can be molded into a pillow shape
0.8 kg of elastic granules containing the urethane prepolymer was filled in a thick polyurethane sheet. Since the filling amount affects the hardness of the core layer (core material) of the pillow, it is adjusted appropriately. The upper mold was placed on the upper part of the same 12 mm thick polyurethane sheet covered with the upper mold, and heat-molded at 150 ° C. in the presence of steam according to a conventional method.

A partially cutaway perspective view of an example of a pillow product is shown in FIG. FIG. 2 is an enlarged view of part A in FIG. In this pillow 1, a core layer 2 is a solidified layer of a foamed resin elastic particle of polyurethane foam made of a urethane binder, and a surface layer 3 is a polyurethane foam layer. When the polyurethane foam layer of the surface layer 3 is continuous to the inside instead of the core layer 2, it is too soft, which is not preferable. However, since the core layer 2 is made of polyurethane elastic particles solidified with a urethane prepolymer binder. ,
Demonstrate a moderately hard elasticity.

Since the present invention is molded with a mold, it can be formed into a three-dimensional free shape. For example, the cushion 4 shown in FIG.
Alternatively, the shape of the mat 5 shown in FIG.

When a polyurethane foam layer having continuous pores is used for the core layer 2 and the surface layer 3, in particular, the air permeability is good, and as shown in FIG. You can easily remove the dirt by dropping it down in time.

[0019]

EFFECT OF THE INVENTION In the molding method using the expanded resin elastic particles of the present invention, a method in which the expanded resin elastic body is granulated into a predetermined size at room temperature using a cutting means is used for the core layer. Therefore, even if the flexible polyurethane continuous foam is used for the surface layer, pillows and cushions having appropriate hardness can be manufactured. Further, since it is granulated into a predetermined size at room temperature, it can be manufactured at low cost.

The molded product of the present invention has excellent breathability, elasticity, and soft elasticity.
Moreover, it has excellent hygroscopicity. In addition, it is possible to wash at home using water.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view of a product example of a pillow.

FIG. 2 is an enlarged view of a portion A in FIG.

FIG. 3 is a perspective view of an example of a cushion product.

FIG. 4 is a perspective view of an example of a mat product.

FIG. 5 is a perspective view of a polyurethane foam block.

FIG. 6 is a perspective view of a foamed resin elastic particle.

[Explanation of symbols]

1 pillow 2 core layers 3 surface 4 cushion 5 mats 10 Polyurethane continuous foam block 11 Expanded resin elastic granules

Front page continuation (58) Fields surveyed (Int.Cl. ⁷ , DB name) B68G 1/00-15/00 B29C 39/00-39/24 B29C 39/38-39/44 B29C 43/00-43 / 34 B29C 43/44-43/48 B29C 43/52-43/58 B29C 67/20-67/24 B29D 30/00-30/72

Claims (6)

(57) [Claims] 1. A cutting granulation step of granulating a foamed resin elastic body into a predetermined size at room temperature using a cutting means, and adding a urethane prepolymer as a binder to the elastic granules obtained in the step. Steps, placing a pre-made polyurethane sheet on the lower mold contact surface side, filling elastic granules containing the urethane prepolymer, and placing the upper mold with the polyurethane sheet covered on top and steaming A molding method using elastic foamed resin particles, which comprises a step of heat-molding in the presence. 2. The molding method using the foamed resin elastic particles according to claim 1, wherein the foamed resin elastic body is a polyurethane foam. 3. The molding method using the expanded resin elastic particles according to claim 1, wherein the expanded resin elastic particles have a particle diameter of 4 to 8 mm. 4. A molded article in which the core layer is a solidified layer of expanded resin elastic particles with a urethane binder, and the surface layer is a polyurethane foam layer. 5. The molded product according to claim 4, wherein the core layer is a solidified layer of polyurethane foam granules with a urethane binder, and the surface layer is a polyurethane foam layer, which has a pillow, cushion, or mat shape. 6. The core layer and the surface layer have continuous pores.
Alternatively, the molded article according to item 5.